Name: CVE-2025-5991: Use After Free
Creator: Rapid7
Published: 2025-06-11T00:00:00.000Z
License: https://www.rapid7.com/legal/website-terms-of-use/
Keywords: CVE, CVE-2025-5991, CWE-416, CVSS 2.1, EPSS 0.00136

There is a "Use After Free" vulnerability in Qt's QHttp2ProtocolHandler in the QtNetwork module. This only affects HTTP/2 handling, HTTP handling is not affected by this at all. This happens due to a race condition between how QHttp2Stream uploads the body of a POST request and the simultaneous handling of HTTP error responses.

This issue only affects Qt 6.9.0 and has been fixed for Qt 6.9.1.

CVSS Details

CVSS 4.0 Base Score: 2.1 (LOW)
CVSS 4.0 Vector: (CVSS:4.0/AV:L/AC:H/AT:N/PR:N/UI:N/VC:L/VI:L/VA:L/SC:L/SI:L/SA:L/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X)

Covered by Rapid7

Product	Vendor Advisory	Solution File	Added	Published
Debian	—	No solution exists	Jun 13, 2025	Jun 11, 2025
Ubuntu	—	No solution exists	Jul 25, 2025	Jun 11, 2025

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CVSS Details

Covered by Rapid7

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